The $146 billion stimulus package intended to jolt the economy by giving taxpayers rebates up to $1,200 includes cash returns for illegal immigrants who pay taxes.

Under the plan passed by the House, illegal immigrants who qualify as "resident aliens" and earned a minimum of $3,000 would be eligible for rebates of between $300-$600, FOX News has learned.

Only those illegals who have been assigned an Individual Tax Identification Number that allows them to file income taxes would be eligible. Resident aliens are defined as people who spend a "substantial" amount of time in the U.S. and have not been deported.

The provision has irked illegal immigration opponents, who say the assigning of TINs and collection of taxes from illegals sanctions their presence in the country.

Rep. Tom Tancredo, R-Colo., told FOX News that the bill will certainly stimulate "more illegal immigration."

The stimulus plan met with overwhelming bipartisan support Tuesday, passing the House 385-35 with little debate after House leaders and White House negotiators came to agreement last week.

Opponents of the illegal immigrant eligibility provision point out that the House considered the bill under "suspension of the rules." Suspension provisions allow the House to expedite bills and don't open them up to the usual amendment process.

The plan, which would send at least some rebate to anyone with at least $3,000 in income— with more going to families with children and less going to wealthier taxpayers — faces an uncertain future in the Senate.

Senate Democrats and some Republicans support a larger package that adds billions of dollars for senior citizens and the unemployed, and reduces the rebate for individuals to $500 and $1,000 for couples.

The Senate version written by Finance Committee Chairman Max Baucus would deliver checks even to the richest taxpayers, who are disqualified under the House-passed measure.

Senate Majority Leader Harry Reid blasted the proposal to send rebates to those with higher incomes, saying it "causes me to want to gag." The feeling is widespread among Democrats, he added, saying the "the gag reflex is coming upon everybody" over the plan.

President Bush and House leaders urged the Senate to take the bipartisan agreement and pass it quickly, even as Baucus, D-Mont., planned a Wednesday vote in his committee on a larger package that could face a slower path.

"We need to get this bill out of the Senate and on my desk," Bush said in the Oval Office.

Congressional leaders are aiming to send the measure to Bush by Feb. 15. But the divergent plans — and bids by Senate Democrats and Republicans to swell the package with more add-ons — could drag out that schedule.

House Speaker Nancy Pelosi, D-Calif., said she hoped the Senate would "take this bill and run with it."

Reid, D-Nev., said that was unlikely in the freewheeling Senate, where members have elaborate wish-lists for adding to the bill, including food stamps, Medicaid and heating assistance for low-income people and spending on infrastructure projects, among other things.

"I think that there's 51 Democratic senators without exception who believe this package can be made better," Reid said, adding that he also expected to have enough GOP support to change it.

Sen. Mitch McConnell, R-Ky., the minority leader, said reopening the deal would be inappropriate.

"This is not a time to get into some kind of testing of wills between the two congressional bodies. This is a time to show we can rise above partisanship, do something important, and do it quickly," McConnell said.

The House plan brought together Democrats and Republicans, both of whom surrendered cherished proposals to reach a deal and cautioned against adding items that could hinder an economic recovery or scuttle the agreement.

"It's important that this bill not get overloaded. I have a full agenda of things I would like to have in the package, but we have to contain the price," Pelosi said. "We made a decision, because that's where we could find our common ground."

Americans "expect us to find ways to work together, not reasons to fight with each other," said Rep. John A. Boehner, R-Ohio, who forged the agreement with Pelosi in consultation with Treasury Secretary Henry M. Paulson.

"The sooner we get this relief in the hands of the American people, the sooner they can begin to do their job of being good consumers," Boehner said.

The measure would send rebates to some 111 million people, including roughly 35 million families who don't make enough to pay income taxes. Individuals with adjusted gross income of $75,000 and couples making $150,000 would get rebates equal to the taxes they paid, up to $600 for individuals and $1,200 for couples. Those making more than that would see their rebate go down by 5 percent of every dollar of income over the limits.

Taxpayers would get at least $300, even if they paid less than that in taxes — or $600 for couples. That's also the case for those who don't pay income taxes but earn at least $3,000.

All eligible people would get an additional $300 per child.

In the Senate, Baucus' proposal removes the income caps and would send rebates to some 20 million senior citizens not covered by the House plan because they don't have income. Baucus' plan also extends unemployment payments for 13 weeks for those whose benefits have run out, with 26 more weeks available in states with the highest jobless rates.

The Senate measure would restore a business tax break dropped during the House negotiations that would permit corporations suffering losses now to reclaim taxes previously paid.

Both packages include roughly $50 billion worth of tax incentives for businesses to invest in new plants and equipment.

To address the mortgage crisis, the House bill would raise the limit on Federal Housing Administration loans from $362,790 to as high as $729,750 in expensive areas, allowing more subprime mortgage holders to refinance into federally insured loans. To widen the availability of mortgages nationwide, it also would boost the cap on loans that Fannie Mae and Freddie Mac can buy, from $417,000 up to $729,750 in high-cost markets. Those measures would expire at the end of the year.

Sen. Charles Schumer, D-N.Y, said Tuesday that he plans to ensure those changes are part of the Senate stimulus bill.

FOX News' Chad Pergram and The Associated Press contributed to this report.